Why no Luftwaffe-derived engines in Heer vehicles?

[Milosh]

Didn't France produce some Panthers post war? Or were these just captured ones?

 

[Koopernic]

Didn't France produce some Panthers post war? Or were these just captured ones?

They were made up of captured or abandoned Panthers with a few built in occupied Germany. France replaced them in 1950 when its own heavy tank came into use.
The Panther used compressed air to evacuate the gun of smoke and to this day French Armour doesn't use a passive bore evacuator.

 

[Reluctant Poster]

When I quoted Ogorkiewicz in an earlier post, I should have mentioned that he was more than a historian, he was an engineer who has been actively involved in the tank industry for many years. Here is an article he wrote in 1955 in which he advocates for diesels. It is a very comprehensive history of diesel tank engines.
The article is from the July - August 1955 issue of Armor. Issues of this magazine are available for free on Google Books. If you have a strong interest in tanks (and who doesn't?) its well worth joining google books.
He passed away last November at the age of 93.

 

[Milosh]

French assessment of the Panther, French Panther Tanks

 

[Admiral Beez]

French assessment of the Panther, French Panther Tanks

A good article, thanks for posting. One thing that caught my eye straight away...

"On the other hand, the engine was not operable over 1500 km. The average engine life amounted to 1000 km."

Because the Germans had the very good V12 Maybach engines.

So, no, perhaps they didn't? Shermans, many with aircraft-derived engines drove from Normandy to the German border and beyond.

The Chieftain, author of the above French assessment article has this video series showing the published design flaws that impacted the Panther's combat efficiency and potential.

 

[Koopernic]

A good article, thanks for posting. One thing that caught my eye straight away...

"On the other hand, the engine was not operable over 1500 km. The average engine life amounted to 1000 km."
So, no, perhaps they didn't? Shermans, many with aircraft-derived engines drove from Normandy to the German border and beyond.

The Chieftain, author of the above French assessment article has this video series showing the published design flaws that impacted the Panther's combat efficiency and potential.

This is not a great translation. Id say they mean there was a major service interval at 1000km.

 

[Admiral Beez]

This is not a great translation. Id say they mean there was a major service interval at 1000km.

I wonder how many Panthers made it to 1,000 km.

 

[Shortround6]

There is a problem with average life. For every engine that craps out at 500km another one has to go to 1500km to get that 1000km average.
I am not saying the Panther driveline was great. Just pointing out the words next to numbers are important to make sure we are comparing the same thing.

 

[swampyankee]

I wonder how many Panthers made it to 1,000 km.

I'd estimate that 1,000 km would be something like 50 to 100 operating hours. The reports I heard about the AVDS-1790 in the early 1980s, an engine built and operated in peacetime, are on that order, with MTBR of about 25 hours and TBOH of about 250. Considering that the AVDS-1790 wasn't being built by slave labor under significant resource constraints, 50 to 100 hours is probably about right for the Maybach's TBOH.

How many Panthers (and Tiger IIs) were abandoned due to mechanical failures? Since the Germans were largely in retreat, after Kursk in the East and Normandy in the West, many of those would be completely lost to the Germans, just as effectively as if they had been destroyed in combat.

 

[Shortround6]

Well, mechanical failure includes the clutch/s, transmission, steering gear/brakes, and the track system/suspension.
Maybe the engine was terrible, I don't know, but there a lot of other reports of other mechanical problems.
Just for information one book claimed the Matilda's steering clutches lasted about 600 miles.
There was quite a bit of debate about the automatic transmissions in the American tanks. Points include cost, size, difficulty of repairs. But it was easier to train drivers. Break downs may have been less common to begin with. We all know or have heard of someone who destroyed the clutch in a car in 10-12,000 miles.
Some tanks have a clutch between the engine and transmission plus a clutch between the transmission and each track.
Are we talking about failures of the Maybach engine itself, failures of the powerpack/installation or what?

 

[Admiral Beez]

How many Panthers (and Tiger IIs) were abandoned due to mechanical failures? Since the Germans were largely in retreat, after Kursk in the East and Normandy in the West, many of those would be completely lost to the Germans, just as effectively as if they had been destroyed in combat.

Even worse when they're turned against you.

 

[Koopernic]

I wonder how many Panthers made it to 1,000 km.

Exactly 50% If the French translation to average has any meaning. It sounds like a bit of a guess.

What smells about this is that no one runs a tank till breakdown. They work out how long 95%-99% will last and then inspect the part to make an assessment to see if maintenance is required or can wait a little or they perform maintenance as scheduled. Parts that are wearing out rapidly should be reported to the manufacturer for improvement. No one is likely to 'run till breakdown'.

If they lasted on average 1000km with a maximum of 1500 km and assuming a gaussian/bell curve distribution one would assume you could rely on around 99% reaching 500km and a few exceeding 1500km. There would be a few 'infant deaths' from early failures from unestablished quality control in the factory.

To me it sound like maintenance involved pulling out the engine with a Bergpanther acting as a crane and replacing it. The removed engine would have maintenance performed in a depot. There would be records of how long it had run and the nature of the maintenance adjusted accordingly. Maybe it would be thrown out.

1 Maybe Regrind valve seats and valves to remove deposits.
2 Maybe Replace Valve stem guides.
3 Maybe replace head gasket or other seals.
4 Maybe replace valves themselves
Some of the above problems would be related to use of second rate materials. I believe British engines used nickel alloys in the valve seats.

The problem with the Panthers final drive gearbox is well known. The Panther used straight cut gears. The Sherman used Herringbone gears because this is more reliable since multiple teeth engage. The T-34 used a planetary gearbox. The final scheduled Pather Ausf F with the Tiger II style schmalturn turret was supposed to get a planetary gearbox since its weight had grown to 50 tons. The use of straight gut gears was apparently a issue with shortage of machine tools but there may have been other issues such as inadequate lubrication flows. I believe the engine of the Sherman racked out and was easily accessible without removal from the tank. That changes how you do maintenance.

This is from Wikipedia:

General Heinz Guderian reported on 5 March 1944:

The frontline reports said service life of the tank's engine had increased up from 700 to 1,000km [435 to 621 miles]. Plus, the same Panther tank-equipped units reported that failures regarding final drive, transmission and steering gears were within a suitable range.​

He further noted a specific instance of mechanical reliability:

From 6 March to 15 April 1944, the 1.Abteilung/Panzerregiment 2 (1st Battalion, 2nd Panzer Regiment) reported a distance of between 1500 km to 1800 km. Four of their seven Panthers was still combat ready without any transmission or engine failure.​

On 22 April 1944, the same battalion reported how a good driver and commander can improve reliability:

This kept in mind, the battalion reported PzKpfw V Chassis No. 154338, Engine No. 8322046 reading 1,878km with driver Obergrefeiter Gablewski, 4.Kp/PzRgt 2. The vehicle was still totally operational. All items were in great condition but the tracks. The consumption of the engine has been 10ltr per 100km. The vehicle was still operating with its first engine and transmission.​

After that report from the units, the Inspector General of Armored Troops acknowledged this in a report, at 1944.05.06.: Der Generalinspekteur der Panzertruppen -Leitender Kraftfahrzeugoffizer- Bb Nr. 3177/44

The report confirms the opinion that thanks to the continuous improvement of its components, the life of the Panther tank has increased. The average lifespan of a Panther can now be roughly equal to that of a Panzer IV with around 1,500 - 2,000 kilometers between two major repair and maintenance processes.​

And,​

gearboxes also have a longer life. Even so, in several cases, at approximately 1500 km, the gear has broken down and the boxes have had to be replaced.​

An example of Panther reliability appeared in the June 1944 edition of Nachrichtenblatt der Panzertruppen (Armoured Troops Bulletin), from a Panther-recovery tank driver's report:

Unteroffizier Krause of a Panther workshop platoon has driven his Panther recovery tank – Chassis No. 212132 – 4,200km until 3 May 1944 without any needing to replace any parts. About 1,000km of this was made towing another Panther tank. The vehicle and engine are still in great condition and operational​

On 28 June 1944, Guderian reported:

Regarding the experiences in opposing the Allied landing in Normandy: The Panzer IV, Panzer V Panther, and Panzer VI Tiger have proven to be successful. The Panther is inclined to catch fire quickly. The lifetime of the Panther's engines (1400 to 1500 km) is much higher than the Panther's final drives. A solution to the final drive teething is immediately needed.​

In September and October 1944, a number of modifications were fitted into the final drives as countermeasures to the reported problems including worn gear teeth, parts, bearings, and insufficient lubrication.


Its easy to see that many of the improvements available to the Panther were identified not introduced fully in the production line due to shortages.

 

[Shortround6]

Engines by themselves rarely catch fire. Leaky fuel lines, sealed engine compartments that hold leaking fluids, poor materials/installation do catch fire.

Transmissions that are designed for 40 ton tanks tend not to work well with 45-50 ton tanks (or transmissions designed for 30 ton tanks installed in 40-45 ton tanks, T-34 and KV).

Skilled, careful drivers can extend the life of mechanical components. Some of this is understanding what the parts are doing and how they need to be operated to get the best life.
My Grandfather was a skilled machinist of the old school. He didn't believe a man was a machinist unless he could disassemble his machine/s, fix them and reassemble them.
He also managed to get about 100,000 miles on a clutch on a 57 chevy Six with a 3 speed manual transmission. No riding the clutch, shifts made smoothly and shifts made when needed. (He did tend to lug the engine of a Volvo that replaced the Chevy). He may have even picked routes that minimized starting on hills in town

But when he started driving some cars still had no synchromesh on all gears, not just first and some trucks used chain drive to the rear axle.
Some drivers understand their vehicles and some don't. I rode with one driver on the fire dept that was either foot full on the gas pedal or full on the brake, He was hard to follow in another truck and nauseating to ride with.

Needing good or expert drivers to get adequate life from the drive line is not really a good plan. Too many drivers are going to be just average.

 

[Koopernic]

I wonder how many Panthers made it to 1,000 km.

Exactly 50% If the French translation to average is accurate.

Engines by themselves rarely catch fire. Leaky fuel lines, sealed engine compartments that hold leaking fluids, poor materials/installation do catch fire.

Transmissions that are designed for 40 ton tanks tend not to work well with 45-50 ton tanks (or transmissions designed for 30 ton tanks installed in 40-45 ton tanks, T-34 and KV).

Skilled, careful drivers can extend the life of mechanical components. Some of this is understanding what the parts are doing and how they need to be operated to get the best life.
My Grandfather was a skilled machinist of the old school. He didn't believe a man was a machinist unless he could disassemble his machine/s, fix them and reassemble them.
He also managed to get about 100,000 miles on a clutch on a 57 chevy Six with a 3 speed manual transmission. No riding the clutch, shifts made smoothly and shifts made when needed. (He did tend to lug the engine of a Volvo that replaced the Chevy). He may have even picked routes that minimized starting on hills in town

But when he started driving some cars still had no synchromesh on all gears, not just first and some trucks used chain drive to the rear axle.
Some drivers understand their vehicles and some don't. I rode with one driver on the fire dept that was either foot full on the gas pedal or full on the brake, He was hard to follow in another truck and nauseating to ride with.

Needing good or expert drivers to get adequate life from the drive line is not really a good plan. Too many drivers are going to be just average.

Germany was certainly and automotive nation but not like the united states, few of the 18 year olds introduced into driving a tank had driving experience.

The original Panther's requests for tender was a 35 ton tank and yes they ended up with a 45 ton tank for Ausfuherung D (Issue D the first model). Adding 2cm of armour plate to the glacis and mantlet as Adolf Hitler requested works out at 1225kg. I calculate 8.5 square meters of 2cm armour at 144kg/sqm. Even allowing for a knock on compounding effect of 100% the armour increase could only cause 2.45 tons of an 10 ton growth. The reality was that a 35 ton tank specification was too light for what was required to begin with.

It was also no point as the Panzer IV with 48 calibre was already providing a potent 7.5cm Anti Tank Gun and the StuG III good Infantry support. The 8cm Panther Armour sloped back at 55 degress, almost 60, could not be penetrated by the Soviet 85mm. At 500m APDS tungsten ammunition fired from the 17 pounder mostly bounced of (late war German armour was depleted in molybdenum). Even the US 90mm wasn't a certainty so that 2cm increase was worth it.

The original Panther tank MAN design had a planetary gearbox. I doubt that had production proceeded on this basis that the relatively minor and sensible weight growth of the Panther would have created problems. The process of radical shortcuts, such as a spur gear instead of planetary for production was aggressively pushed forward, sometimes against the wishes of designers and army officers, by the Chief Director of Armament and War Production Karl Otto Sauer.

It was predicated on a target of 600 tanks/month. Since they never even achieved 280 they could have probably stuck to a proper gear box.

I recall reading that the office forced BMW to reduced the number of turbine blades in the BMW 003 engine from 72 to 62. It would seem they sometimes introduced so many reliability problems and disruptions.

Remove the bad gearbox, its poor materials and most of the Panther problems go. Remove the substandard fuel lines that leaked fuel vapours many of the remainder of the problems go. Wheels not properly alloyed or hardened would have fixed another problem.

I've read that Reliability rate is an generalized term made up by Zaloga, the Panther goes through parts the same as a Sherman. It seems the issue was mean time to repair.

 

[Reluctant Poster]

Exactly 50% If the French translation to average is accurate.


Germany was certainly and automotive nation but not like the united states, few of the 18 year olds introduced into driving a tank had driving experience.

The original Panther's requests for tender was a 35 ton tank and yes they ended up with a 45 ton tank for Ausfuherung D (Issue D the first model). Adding 2cm of armour plate to the glacis and mantlet as Adolf Hitler requested works out at 1225kg. I calculate 8.5 square meters of 2cm armour at 144kg/sqm. Even allowing for a knock on compounding effect of 100% the armour increase could only cause 2.45 tons of an 10 ton growth. The reality was that a 35 ton tank specification was too light for what was required to begin with.

It was also no point as the Panzer IV with 48 calibre was already providing a potent 7.5cm Anti Tank Gun and the StuG III good Infantry support. The 8cm Panther Armour sloped back at 55 degress, almost 60, could not be penetrated by the Soviet 85mm. At 500m APDS tungsten ammunition fired from the 17 pounder mostly bounced of (late war German armour was depleted in molybdenum). Even the US 90mm wasn't a certainty so that 2cm increase was worth it.

The original Panther tank MAN design had a planetary gearbox. I doubt that had production proceeded on this basis that the relatively minor and sensible weight growth of the Panther would have created problems. The process of radical shortcuts, such as a spur gear instead of planetary for production was aggressively pushed forward, sometimes against the wishes of designers and army officers, by the Chief Director of Armament and War Production Karl Otto Sauer.

It was predicated on a target of 600 tanks/month. Since they never even achieved 280 they could have probably stuck to a proper gear box.

I recall reading that the office forced BMW to reduced the number of turbine blades in the BMW 003 engine from 72 to 62. It would seem they sometimes introduced so many reliability problems and disruptions.

Remove the bad gearbox, its poor materials and most of the Panther problems go. Remove the substandard fuel lines that leaked fuel vapours many of the remainder of the problems go. Wheels not properly alloyed or hardened would have fixed another problem.

I've read that Reliability rate is an generalized term made up by Zaloga, the Panther goes through parts the same as a Sherman. It seems the issue was mean time to repair.

The RAF destruction of the ZF gearbox plant didn't help. From the USSBS:

 

[Koopernic]

The RAF destruction of the ZF gearbox plant didn't help. From the USSBS:


View attachment 582606

Apparently also caused serious spare parts and maintenance problems
that lead to cannibalisation of Panthers to keep others going.

 

[Koopernic]

Having Maybach and Praga focus primarily on AFVs helped to keep the much-needed aircraft engines going to aircraft.

By the way, Daimler's MB500 series marine diesels were based on the DB600 engine.

The Panzer VIII Maus (mouse) 188 ton super heavy tank was to be powered by the MB507 a diesel version of the DB603. This wasn't considered enough and the Maus was upgraded to the 895kW MB517 which was a turbo supercharged version of the above. These engines were primary used for marine applications. The tank may have been big but could cross bridges by being on a train. The 895kW engine used 7.6 tons worth of DC generator and DC motor to power the tracks. Each track had its own DC motor and own DC generator though the DC generators were integrated into one unit.

Mercedes-Benz 500 Series Diesel Marine Engines

 

[WARSPITER]

The Maybach engine had another wear and tear problem in the Panther as any engine would due to the poor hydraulic turret rotation system
which was dependant on engine RPM. In other words to get the turret turning at speed in combat conditions you needed to rev the engine
as high as 3000rpm. This had to be done by the driver while the gunner controlled the the turret - a messy method. The engine revs were eventually
governed back to around 2500 which slowed turret turning again (this was an attempt to increase engine life).

This was another factor which made the Panther a poor assault vehicle and which helped to chew up the engine life.

 

[spicmart]

Wasn't the maintenance of inverted V-engines much more difficult than that of upright Vs because of the pistons being downwards?

 

[swampyankee]

Wasn't the maintenance of inverted V-engines much more difficult than that of upright Vs because of the pistons being downwards?

Probably not so much in aircraft (although oil collection in the cylinders would likely be as much a problem in inverted V-12s as in radials), but it would be a noticeable pain in ground vehicle and marine installations. On the other hand, conversion for right-side up upright use would probably be fairly straightforward, albeit not trivial.